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US 4,048,545 AGranted
Cathode ray tube processing
AssigneeUnion Carbide Corporation
InventorsThomas Harry Madden, Clair Wilbur Reash
Life of this patent
Estimating the term…
Abstract
A method for treating and gettering a reworked television picture tube using CO.sub.2 and water vapor which avoids the development of deleterious high pressures upon the regettering thereof.
Claims2
Method for treating and gettering a picture tube which has been previously gettered by flashing of a barium-containing material therein and which as a result of said flashing has a barium film on portions of its internal surface, said method comprising:
- i. converting said barium film to barium carbonate by contacting the barium film on the inner surface of said previously gettered picture tube with a gas mixture consisting essentially of CO.sub.2 and water vapor said gas mixture being at least about 10% by volume of CO.sub.2 and said water vapor being in an amount of at least about 1% of the volume of CO.sub.2 but less than the amount which corresponds to the dew point of water vapor in said mixture,
- ii. subsequently evacuating said picture tube to a pre-gettering vacuum and
- iii. gettering said picture tube by flashing a barium-containing getter therein.
Dependencies are inferred from the claim text.